SALT LAKE CITY — There’s something new to pay attention to the next time you approach an intersection that has a left turn signal.

For years, there were the "left-on-green-arrow-only" turn signals. Once the arrow went red, you had to sit until the next cycle. Other signals, after giving the green arrow, allow a left turn as long as you yield to oncoming traffic.

Now there’s another type of left turn arrow — it’s yellow and it flashes.

These signals have been installed in Utah and a number of other states for several years now.

"This flashing yellow arrow is our new standard. Our new signals will be designed to use this signal," says Robert Miles, UDOT’s Region 2 traffic engineer.

The left turn signals have 4 positions:

Steady green arrow: the motorist can proceed with left turn.

Flashing yellow arrow: Pull into intersection and turn after yielding to approaching traffic and pedestrians.

Solid yellow arrow: Drivers should not enter the intersection if they can stop safely.

Steady red arrow: Drivers stop and wait.

“The flashing yellow arrow configuration has a little more flexibility than the old five-section head”, Miles said. “It allows us to vary things by time of day to meet the traffic need a little more effectively.”

Take, for example, the Salt Lake intersection at 600 North and 400 West. It’s extremely busy at times with semis and gravel trucks coming off the freeway and making left turns onto northbound 400 West. The signals have been set to allow longer left turn times, keeping the trucks moving along, without delaying other motorists.

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There are about a thousand of these flashing yellow signals in use throughout the country. And, national statistics have shown a 30 percent reduction in left turn collisions.

In Utah, the old signals will still be used, but whenever new intersections are constructed or rebuilt, look for the new yellow flashers.

"It's in everybody's best interest if we can keep things efficient," Miles said.

UDOT has just released a brochure explaining how the left turn signals work. They’re available for download on www.udot.utah.gov.